An agricultural harvester known as a “combine” is historically termed such because it combines multiple harvesting functions within a single harvesting unit, such as picking, threshing, separating, and cleaning. A combine includes a header which removes the crop from a field, and a feeder housing which transports the crop matter into a threshing rotor. The threshing rotor rotates within a perforated housing, which may be in the form of adjustable concaves, and performs a threshing operation on the crop to remove the grain. Once the grain is threshed it falls through perforations in the concaves onto a grain pan. From the grain pan the grain is cleaned using a cleaning system, and is then transported to a grain tank onboard the combine. A cleaning fan blows air through the sieves to discharge chaff and other debris toward the rear of the combine. Non-grain crop material such as straw from the threshing section proceeds through a residue handling system, which may utilize a straw chopper to process the non-grain material and direct it out the rear of the combine. When the grain tank becomes full, the combine is positioned adjacent to a vehicle into which the grain is to be unloaded, such as a semi-trailer, gravity box, straight truck, or the like, and an unloading system on the combine is actuated to transfer the grain into the vehicle.
More particularly, a rotary threshing or separating system of a combine includes one or more rotors that can extend axially (front to rear) or transversely (side to side) within the body of the combine, and which are partially or fully surrounded by perforated concaves. The crop material is threshed and separated by the rotation of the rotor within the concaves. Coarser non-grain crop material such as stalks and leaves pass through a straw beater to remove any remaining grains, and then are transported to the rear of the combine and discharged back to the field. The separated grain, together with some finer non-grain crop material such as chaff, dust, straw, and other crop residue are discharged through the concaves and fall onto a grain pan where they are transported to a cleaning system. Alternatively, the grain and finer non-grain crop material may also fall directly onto the cleaning system itself.
A cleaning system further separates the grain from non-grain crop material, and typically includes a fan directing an airflow stream upwardly and rearwardly through vertically arranged sieves which oscillate in a fore and aft manner. The airflow stream lifts and carries the lighter non-grain crop material towards the rear end of the combine for discharge to the field. Clean grain, being heavier, and larger pieces of non-grain crop material, which are not carried away by the airflow stream, fall onto a surface of an upper sieve (also known as a chaffer sieve), where some or all of the clean grain passes through to a lower sieve (also known as a cleaning sieve). Grain and non-grain crop material remaining on the upper and lower sieves are physically separated by the reciprocating action of the sieves as the material moves rearwardly. Any grain and/or non-grain crop material which passes through the upper sieve, but does not pass through the lower sieve, is directed to a tailings pan. Grain falling through the lower sieve lands on a bottom pan of the cleaning system, where it is conveyed forwardly toward a clean grain auger. The clean grain auger conveys the grain to a grain elevator, which transports the grain upwards to a grain tank for temporary storage. The grain accumulates to the point where the grain tank is full and is discharged to an adjacent vehicle such as a semi trailer, gravity box, straight truck or the like by an unloading system on the combine that is actuated to transfer grain into the vehicle.
Meanwhile, incompletely cleaned grain, called tailings, may include incompletely threshed or unthreshed crop, free grains of completely threshed crop, and other plant material or Material Other than Grain (MOG). Such tailings from the upper or lower sieve having fallen onto the tailings auger pan are recycled through the cleaning system. Often, a return auger or tailings conveyance receives the tailings from a tailings auger at the forward end of the auger pan, and lifts the tailings vertically in order to recycle the tailings through the threshing and separating and/or cleaning system.
Harvesting crops using a combine of the above description often results in the loss onto the ground of a certain amount of grain or corn, which is called harvest loss. Harvest loss may be due to incorrect operation of the combine, such as the travel speed being too fast or too slow, or lack of proper optimization of the settings of the header mechanisms, such as the height at which the header is positioned above the ground being too high or too low, as non-limiting examples. Further, the header of the combine may experience a mechanical failure, such as a leak, leading to harvest loss. This harvest loss, coupled with loss onto the ground of grain or corn prior to harvesting due, for example, to insect damage, disease, or weather, called pre-harvest loss, results in significant economic loss to agricultural producers. Currently, there is no automatic method to determine harvest loss that occurs at the header, or to distinguish harvest loss from pre-harvest loss.
As a result, an operator of a combine may proceed to incorrectly operate the combine, fail to optimize the settings of the header mechanisms, or continue to operate the header following a mechanical failure for an extended time, greatly exacerbating overall crop loss. Further, when the operator of the combine makes an adjustment from the cab, he or she does not immediately receive feedback of the positive or negative effect on harvest loss that results from the adjustment. Often, the operator is required to dismount from the combine and conduct a manual investigation on the ground surface to determine the effectiveness of the adjusted settings. Even under this condition, it may be difficult for the operator to distinguish harvest loss from pre-harvest loss. Additionally, attempts by the operator to observe harvest loss from the cab of the combine during operation may distract the operator, resulting in unsafe operation of the combine.
The economic impact of harvest loss, as well as pre-harvest loss, is considerable. At the time of this application, corn sells for approximately $7.00 per bushel. Reasonable harvest losses may be, for example, 3% or one to two bushels per acre. An operator harvesting a hundred acre field, therefore, may leave a thousand dollars' worth of corn on the field under optimal circumstances. Small changes to the position of the header, or in the case of a wheat header to the speed of the rotatable reel, can double or triple grain loss. Undetected, continued incorrect operation of the combine, failure to optimize the settings of the header mechanisms, or continued operation of the header following a mechanical failure, results in thousands of dollars of additional economic losses to the aforementioned operator. Cumulatively, saving only one bushel of crop loss per acre in the United States may add tens of millions of bushels to the grain supply, and may collectively add hundreds of millions of dollars of potential revenue to agricultural producers.
What is needed in the art, therefore, is an automatic system or method to determine harvest loss that occurs at the header, and/or to distinguish harvest loss from pre-harvest loss. What is further needed in the art is an automatic system or method that senses harvest loss and pre-harvest loss, and provides information regarding the type, source, and location of harvest loss and pre-harvest loss, so that the operator of the combine may optimize various settings of the header and combine, such as the height at which the header is maintained above the ground, the travel speed of the combine, and other settings of mechanisms of the header, while receiving useful feedback regarding the effectiveness of the adjustments.